Ethernet has become the dominant form of transmission of data in networks. The majority of applications involve point to point copper or fiber links with rates varying between 1 Mbit/sec to 100 Mbits/sec, while 400 Gbits/sec Ethernet is under standardization. Due to interoperability concerns Ethernet rates are always fixed mostly in multiples of 10. Physical layer devices (PHYs) can negotiate to communicate at one of the predetermined standard rates: e.g. between 1 Gbit/sec and 10 Gbit/sec. This convention which served the industry well to date, is necessitated mainly by the need to facilitate interoperability between PHYs manufactured by different vendors. However it limits the capacity of networks, by fixing the rate of the links to that prescribed of a standard iteration (i.e. 10 Mbps, 100 Mbps, 1 Gbps, 10 Gbps, 40 Gbps, 100 Gbps, 400 Gbps). That coarse quantization of the data rate leaves a significant portion of the available channel capacity unused, and increases overall cost. For example an Ethernet transceiver rated for 10 Gbps operation can operate at a significantly increased data rate when it interfaces to a channel that has smaller loss than the worst case specification. Moreover, the power dissipation of a transceiver can be significantly reduced when operating at a lower rate, under light traffic conditions. The inefficiency imposed by coarse data rate quantization is suboptimal for large scale datacenter computing, as well as for many other applications. However, the industry standards cannot accommodate “granular rate Ethernet” (or e.g. “granular rate PCIexpress”) due to interoperability and complexity concerns—variable rate at the physical layer lever would complicate the design of all network elements: Network Interface Cards (NICs), Switches, Physical Layer Transceiver Devices (PHYs) and Optical Transponder Modules. As a result all Networking Integrated Circuits today operate at one of the predetermined standard rates, despite increased signaling bandwidth available via a higher but non-standard rate on a given channel, or the power savings or other efficiency gain of a lower non-standard rate. The same restrictions apply to all other link level protocols such as PCIe, FibreChannel, SerialRapidIO, CPRI, OBSAI etc.